Today at 3:02 CST is when the sun will be in Libra and Autumn/Mabon will have officially started. Mabon is a time of harvest, thanksgiving, and when day/night is equal which can mean to bring your shadows into the light.
Tonight I am going to attend my first online Mabon ritual celebration (normally I just do one by myself) and we will be be addressing our shadow side by looking at a problem we have, thanking for the lesson, and then resolving it.
No matter how you celebrate Mabon, the important thing is balance. Whether you meditate, create an altar, or go out with a full ritual remember both light and dark are important in ourselves.
Today doesn't feel like physical Autumn though since here in Wisconsin it is in the mid 80's. The leaves are about 40% changed so it doesn't look too much like it, but here is a picture of our first tree that is always the first to change. Hope the others follow after it soon along with the cooler nights.